A funny joke

I thought this one was funny:

After numerous rounds of “We don’t know if Osama is still alive”, Osama
himself decided to send George Bush a letter in his own handwriting to let
him know he was still in the game. Bush opened the letter and it appeared
to contain a single line of coded message:

370HSSV-0773H

Bush was baffled, so he e-mailed it to Condi Rice. Condi and her aides had
no clue either, so they sent it to the FBI. No one could solve it at the
FBI so it went to the CIA, then to the NSA. With no clue as to its meaning
they eventually asked Britain’s MI-6 for help. Within a minute MI-6 cabled
the White House with this reply:

“Tell the President he’s holding the message upside down.”

I’ll let you figure it out.